1. Field of the Invention
The present invention relates to a door opening and closing device for a refrigerator having a side-by-side door configuration, and more particularly to a door opening and closing device for a refrigerator, in which both doors are separated from each other to divide gaskets when one door is opened.
2. Description of the Related Art
FIG. 1 is a perspective view of a refrigerator having a conventional door opening and closing device.
As shown in FIG. 1, the refrigerator comprises a refrigerating chamber 1 located in the upper portion thereof, and a freezing chamber 2 located in the lower portion thereof. The above refrigerator is a French-type refrigerator which does not comprise a partition for dividing the refrigerating chamber 1.
Doors 3 for opening and closing the refrigerating chamber 1 are installed in a side-by-side configuration, and gaskets 10 for preventing cold air in the refrigerating chamber 1 from leaking to the outside are installed on the circumferential surface of the doors 3 and contact a refrigerator main body 5.
Side gaskets 11 for preventing cold air in the refrigerating chamber 1 from leaking to the outside are installed on inner side surfaces of doors 3, which contact each other. Generally, a French-type refrigerator has a filler structure in which a filler is installed on one door so that the side gaskets 11 of both doors 3 come into contact, or a fillerless structure in which the side gaskets 11 of both doors 3 contact without a filler.
The refrigerator of FIG. 1 is a fillerless type refrigerator, in which the side gaskets 11 installed on both doors 3 come into contact under the condition that the doors 3 are closed, thereby sealing a gap between the doors 3.
FIG. 2 is a schematic plan view of the conventional refrigerator in a state in which the side gaskets 11 come into contact under the condition that both doors 3 are closed.
Each of the side gaskets 11 has a magnetic body 14 installed therein so as to maintain attractive force between the side gaskets 11. When one door 3 is opened, the opponent door 3 is opened together.
In order to solve the above problem, there is proposed a door separating structure for separating both doors 3 from each other so that both side gaskets 11 are separated from each other when one door 3 is initially opened and when the door 3 is nearly closed.
That is, a hinge unit 15 for connecting the door 3 to the refrigerator main body 5 comprises a hinge link 17 so that the door 3 can horizontally move, i.e., can be translated when the door 3 is opened or closed. Both ends of the hinge link 17 are rotatably connected to a hinge bracket 16 installed on the refrigerator main body 5 and the door 3.
The hinge unit 15 further comprises an elastic member 18 for providing elastic force to the door 3 so that the door 3 contacts the opponent door 3.
A cam member 21 for moving the door 3 by the interference when the door 3 is opened or closed is installed on the refrigerator main body 5, and a cam contact lever 25 contacting the cam member 21 is installed on the door 3. A roller 26, which rolls on the cam member 21, is installed on the cam contact lever 25.
Accordingly, when one door 3 is opened at a small angle, the door 3 is rotated centering on a door hinge shaft 17a. The roller 26 of the cam contact lever 25 moves along the cam plane of the cam member 21 according to the displacement of the door 3. When the roller 26 reaches the vertex of the cam plane, the door 3 is pushed backwards centering on a main body hinge shaft 17b, is separated from the opponent door 3, and is opened under the condition that both side gaskets 11 are separated from each other.
When the door 3 is opened at a larger angle, the door 3 is rotated centering on the door hinge shaft 17a. 
On the other hand, when the door 3 is closed, the roller 26 of the cam contact lever 25 moves along the curved plane of the cam member 21. Thereby, the door 3 is closed under the condition that both side gaskets 11 are separated from each other.
As described above, when the door 3 is opened or closed, since the door 3 is separated from the opponent door 3, the interference between both side gaskets 11 is minimized. Accordingly, it is possible to prevent the temporary opening of one door 3 together with the opening of the opponent door 3 and the rapid abrasion of the side gaskets 11 due to the frequent contact between the side gaskets 11.
In the refrigerator having the above-described conventional door opening and closing device, when the door 3 is closed, as shown in FIG. 4, the roller 26 of the cam contact member 25 collides with the cam member 21, thereby generating noise and impact. Further, when the door 3 is closed, the door 3 is rapidly pushed backwards, thereby drastically decreasing user's tactility when the door 3 is opened or closed.
When the door opening and closing device is used for a long time under the above state, the roller 26 is damaged due to the frequent collision between the roller 26 and the cam member 21, and the gasket separating operation cannot be smoothly performed.
Since the cam member 21 is protruded from the refrigerator main body 5 towards the door 3, when a user opens the door 3, the aesthetic appearance of the refrigerator is poor. Further, in order to reduce impact generated when the door 3 is closed, the cam plane must have a gentle slope and the cam member 21 must have a large protrusion distance.
The above door opening and closing structure is described by “Door opening and closing device for refrigerator” (disclosed in Japanese Patent Laid-open Publication No. 1982-73381). In the structure of the above door opening and closing device, a cam member is protruded forwards from a refrigerator main body. If the cam member is not protruded forwards from the refrigerator main body, a cam profile has a steep gradient, thereby increasing impact and noise when a door is opened or closed.